Fuel Pump Sending Unit Main Harness

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Doppleganger

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Does anyone know where the main harness (from the selector valve on the right side) enters the cab? I have pics before disassembly - there is a main harness going forward on the right side and another that crosses over the crossmember to the left side.

I think part of that crossover harness is for the left tank, but there is a main harness on the left side that is from the tail lamps as well - just cant tell if the plug/harness at the solenoid valve goes forward and into the cab on the left or right side of the frame.

Its a mess enough figuring what wires and fuel lines go where with EFI.

Thx.
 

Old Guy Bill

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On my 78 there are two separate harnesses. The tank wiring is a round plug that goes up the drivers side frame rail and enters the cab below the accelerator cable.
 

CalSgt

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On my 78 there are two separate harnesses. The tank wiring is a round plug that goes up the drivers side frame rail and enters the cab below the accelerator cable.
Pretty sure this is how mine was

IIRC the grommet for that harness actually is a female-female 4 prong plug.

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CalSgt

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Pretty sure this is how mine was

IIRC the grommet for that harness actually is a female-female 4 prong plug.

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Here’s a picture from when I took mine apart, I think it went over the PS frame and back through a grommet in the frame to the switch (not totally sure that was correct though)
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Doppleganger

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Here's one of the pics I have of when I pulled the motor and some of the wiring was exposed. The PO must have gotten a great sale on solid core red wire and fudged it everywhere by cutting out chunks of the original harnesses.....so not sure if what I'm looking for was gone when I got it. I know the Pollack valve didn't work - was stuck on one tank.
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CalSgt

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Here's one of the pics I have of when I pulled the motor and some of the wiring was exposed. The PO must have gotten a great sale on solid core red wire and fudged it everywhere by cutting out chunks of the original harnesses.....so not sure if what I'm looking for was gone when I got it. I know the Pollack valve didn't work - was stuck on one tank.
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I’d gamble the Pink wire coming from the DS frame is the sending unit wire for the gas gauge, I believe it goes to the bulkhead
 

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